Even with the introduction of automated sequencing system, some intermediate steps can be useful for scanning PCR products with the aim to identify the gene fragment potentially mutated and then confirm the mutation by sequencing. The scanning techniques most commonly used for PCR products are single-strand conformation polymorphism (SSPC), enzymatic or chemical cleavage of mismatched base pairs, and differential unfolding of homoduplexes and heteroduplexes by denaturing gradient gel electrophoresis (DGGE). Recently, conformation-sensitive gel electrophoresis (CSGE) has been successfully used as a simple, inexpensive, and highly reliable method for localizing FX mutations[20] (Fig. 4). The combination of PCR-CSGE-sequencing could be useful in family studies where, after complete characterization of the mutation in a family member by sequencing the entire FX gene, the other relatives are screened by means of CSGE only. Although expression studies are invaluable to detect subtle functional differences in the cases where the mutations are antigen positive (i.e., normal antigen levels), they are less useful where the mutations are antigen negative (as is reflected in the low in vivo plasma levels), as the mutant proteins are likely to be unstable or may not be expressed. With the availability of FX crystal structures, sequence alignments and molecular modeling are effective methods in identifying structural perturbations in active sites.[21] Molecular modeling in combination with energy refinements can be an invaluable tool in the assessment of cases in which protein misfolding is the most likely outcome of a given mutation.

Getting Started With Dumbbells

Getting Started With Dumbbells

The use of dumbbells gives you a much more comprehensive strengthening effect because the workout engages your stabilizer muscles, in addition to the muscle you may be pin-pointing. Without all of the belts and artificial stabilizers of a machine, you also engage your core muscles, which are your body's natural stabilizers.

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